Maybe offtopic but is a apologize and maybe a help for new Dreampi users...:
Sorry for my connection issues the last 2 GameNights, (maybe all the Jan month with the fail) but i found the issues later.
My Dreampi problem wasn't the Port Forward or DMZ (i never used it, no need to disable SSH).
The devil here is the CG-NAT that my ISP enabled without any advice in 2021.
This is like a kick in the mouth because all the router config never will work on this aspect, my IP is not public and sure that IPv6 and Dreamcast world are not friends jajajja.
Dreamcast was always in advance of his time, but that is maybe so much jajajja.
Lesson learned kids, spit on your ISP provider if they enable CGNAT.
Again, sorry, I missed last Ooga Booga game night and my revenge with the company will be very big
Have a nice day!!! (Sorry for my bad english)